The invention relates to a sound dampening housing for a rock drill which moves along a feed beam in a longitudinal direction thereof, the sound dampening housing being attachable to the feed beam of the rock drill on its both sides so that together with the feed beam the sound dampening housing constitutes a substantially closed space within which the rock drill and at least a main part of a drill rod outside a hole are located.
When drilling rock, drill rigs are used that comprise one or more booms mounted on a base and a drill movably mounted on a feed beam provided on the boom(s). Often the feed beam is also installed at an end of a boom movably in its longitudinal direction by a separate cradle so as to enable the feed beam to be arranged in a desired position and in a desired direction for drilling. In view of these various movements of the boom and the feed beam, the drill rig is provided with various transfer cylinders or hydraulic motors known per se that are driven by pressure fluid.
A typical problem in rock drilling is noise. The noise is produced by a rock drill impacting on a head of a tool and the tool impacting on rock, as well as by various other movements, such as rotation, etc. The noise, which propagates even quite widely to the neighbourhood, keeps causing more and more problems, particularly in the vicinity of housing areas. In order to prevent the noise from causing restrictions on working hours or sites, attempts have been made to solve the issue particularly in surface drilling by using various noise damping housings around the feed beam and the drill. Such solutions are known e.g. from WO 2006/038850, WO 00/39412, SE 523874, U.S. Pat. No. 3,667,571, and JP 5-295978. The problem with all these solutions is that they are difficult to implement or they do not dampen the noise over the entire area of the drill. In addition, the mechanical apparatuses used for opening the sound dampening housing when replacing or adding a drill rod are complex and laborious. Further, the sound dampening housings are quite large and heavy, which makes them difficult to manufacture and use.